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A slice of s'mores cake layered with marshmallow fluff, graham frosting and chocolate ganache on a black plate.
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MOMOFUKU BANANA S’MORES CAKE

Author: Erika Kwee

Ingredients

Banana cake

  • 1 1/3 cups all-purpose flour
  • 3/4 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1/2 teaspoon kosher salt
  • 1 cup sugar
  • 6 tablespoons unsalted butter at room temperature
  • 1 large egg
  • 1/2 cup buttermilk I used 1/2 cup almond milk + 1/2 tablespoon apple cider vinegar
  • 2 tablespoons olive oil
  • 1/2 teaspoon pure vanilla extract
  • 1 cup ripe banana broken into chunks (I used around 3 medium-small bananas)
  • 1/2 cup chocolate chips mini or regular

Graham cracker crumb:

  • ½ cup graham cracker crumbs about 4 sheets ground in a food processor, if using whole crackers
  • ¼ cup all-purpose flour
  • 2 tablespoon cornstarch
  • 1 tablespoon sugar
  • 1 tablespoon brown sugar
  • ½ teaspoon kosher salt
  • 4 tablespoons butter melted

Graham cracker frosting

  • 1 cups graham cracker crumbs about 8 sheets ground into crumbs
  • 1/3 cup almond milk
  • ¼ teaspoon kosher salt
  • 6 tablespoons unsalted butter at room temperature
  • 1 tablespoons packed brown sugar
  • 1 tablespoons powdered sugar
  • ½ teaspoon ground cinnamon

Milk chocolate ganache

  • ¾ cup milk chocolate chips or Hershey bars
  • 3 tablespoons milk

Marshmallow frosting:

  • ½ cup butter room temperature
  • 2 cups powdered sugar
  • ¼ teaspoon kosher salt
  • ¼ teaspoon vanilla
  • 5 oz mini marshmallows

Instructions

For the banana cake:

  • Preheat oven to 325 degrees and grease a 9x13 pan.
  • In a medium bowl, whisk together all dry ingredients (flour through salt). In another bowl, use an electric mixer to cream together the sugar and butter until light and fluffy, about five minutes. Beat in the egg until thoroughly combined. In a small bowl or measuring cup, whisk together the buttermilk, oil and vanilla. Stream mixture into the butter mixture while beating on low. Increase speed to high and beat for 5-6 minutes until mixture is pale and homogenous. It may look a little grainy, but you want the mixture to be as smooth as possible.
  • Once the mixture is homogenous, add the banana and beat until bananas are broken up. Add the dry ingredients and mix on low until dry ingredients are just barely incorporated and you can still see streak of flour--do not overmix! Fold in the chocolate chips with a spatula and finish mixing the batter by hand until no floury streaks remain.
  • Pour batter into prepared pan and bake for 40-50 minutes (check at 40 minutes and continue baking for 5-7 minute increments until a tester inserted in the middle comes out clean. Cool completely before removing from pan.
  • Use a 6-inch cake ring or template to cut two 6-inch circles out of the cake. Line a six-inch cake pan with plastic wrap and press the remaining cake scraps firmly into the bottom to form your third cake layer. At this point, you can freeze tightly wrap each cake layer (leave the scrap layer in the cake pan) in plastic wrap for easier assembly later.

For the graham cracker crumb:

  • Preheat oven to 300 degrees and line a baking sheet with a silpat or parchment paper.
  • Whisk together all dry ingredients (graham cracker crumbs through salt. Drizzle butter over mixture and gently toss until you get a clumpy, just-moist, mixture with some pea-sized clumps. Pour mixture onto the prepared baking sheet and bake for 20 minutes, stirring once, or until crumbs just start to brown. Remove and cool completely.

For the graham cracker frosting:

  • In a small bowl, beat together the graham cracker crumbs, milk and salt until it achieves the texture of a runny cookie butter. In a separate bowl, use an electric mixer to cream together the butter, sugars and cinnamon. Slowly beat in the graham cracker mixture until fully incorporated into the butter mixture.

For the milk chocolate ganache:

  • Add chocolate chips (or broken up Hershey bars, if using) and milk to a glass measuring cup. Microwave for 45 seconds, then stir mixture until all chocolate has melted. Microwave for an additional 15 seconds if needed to melt the chocolate.

For the marshmallow frosting:

  • Make this frosting right before assembly!
  • In a medium bowl, beat together the butter, sugar, salt and vanilla until creamy. Set aside.
  • Preheat your oven broiler to the highest heat and line a baking sheet with a silpat or greased parchment paper. Pour marshmallows onto prepared pan and broil for about 1 minute or less--keep an eye on the pan the entire time, as marshmallows can go from toasty golden to burnt in seconds. Once golden brown, remove marshmallows from oven and immediately beat them into the butter mixture. Use frosting immediately.

Assembly:

  • Assemble your cake by laying down your bottom cake layer, then spread a thin layer of graham cracker frosting, followed by a thick layer of marshmallow cream. Spread your chocolate ganache on top, then sprinkle some graham cracker crumbs over, making sure they are tightly packed in. Finish with a thicker layer of graham cracker frosting, place your next layer of cake on top, and repeat. Once you've stacked your final layer, spread the fillings the same way that you would on the insides, and sprinkle the remaining graham cracker crumbs above to top it off.